Pandemic-era flat purchases at compressed yields are approaching the five-year mark. Our analysis of 31 million HMLR transactions identifies 282,850 flats still held from the 2020–2021 surge — and quantifies the pricing trap their owners now face.
Flat owners who bought during the 2020–2021 pandemic surge face median price appreciation of just +6.4% over four years — insufficient to cover transaction costs. As they approach the five-year holding threshold identified in our earlier research, they constitute the single largest motivated-seller cohort to form in a decade.
The pandemic housing market produced an anomaly in flat purchases that will define London's resale landscape for the next three years. The stamp duty holiday, interest rate cuts to historic lows, and a brief period of renewed urban appetite combined to drive flat transaction volumes to their highest level in the dataset — 218,059 flats purchased in 2021 alone, against a pre-pandemic annual run-rate of 135,000–174,000.
Transaction volumes by year for flats nationally tell the full story. The 2021 peak dwarfs every prior year in the dataset, with 2020 itself elevated despite the March–May lockdown removing three months of activity.
| Year | Flat transactions | Median price | YoY change |
|---|---|---|---|
| 2019 | 174,336 | £210,000 | — |
| 2020 | 146,148 | £220,875 | +5.2% |
| 2021 ▲ peak | 216,477 | £230,000 | +4.1% |
| 2022 | 208,179 | £236,000 | +2.6% |
| 2023 | 160,849 | £231,288 | −2.0% |
| 2024 | 160,826 | £235,000 | +1.6% |
Source: HMLR Price Paid Data, 31M transactions. All property types, England & Wales.
The critical issue for pandemic-era flat buyers is not simply stagnant prices — it is that their returns have diverged sharply from every other property type. While detached and semi-detached houses benefited from a structural re-rating during the "race for space," flat prices responded modestly and have since partially reversed.
The implication is not symmetrical. House owners purchased equity. Flat owners purchased exposure. As the five-year mark arrives, the psychology of loss-aversion combined with practical pressures — lease erosion, service charge rises, EPC compliance — will push a portion of this cohort to market regardless of return.
Leasehold compounding. A 2021 flat purchase on a 125-year lease now reads 120 years on a title search. At 115 years the cost of extension rises materially. Every year without action increases the urgency — and the likelihood of a motivated sale.
Service charge inflation. Buildings insurance premiums rose 30–50% in 2022–2023 across London leasehold blocks. Management company cost-pass-through has created an annual charge burden that was not modelled into the original purchase. This is a recurring, non-recoverable cost with no offset in capital value.
Matching purchase records to subsequent resale transactions across the same address allows us to identify which pandemic-era buyers have already exited and which remain. The figures are striking.
| Purchase cohort | Properties purchased | Resold since | Still held | Retention rate |
|---|---|---|---|---|
| 2020 (covid surge) | 122,339 | 25,740 | 96,599 | 79% |
| 2021 (peak year) | 218,059 | 31,808 | 186,251 | 85% |
| Combined cohort | 340,398 | 57,548 | 282,850 | 83% |
Source: HMLR Price Paid Data. Retention defined as no subsequent sale record found for the same address.
Of the 340,398 flats purchased in the 2020–2021 window, 282,850 remain in the hands of their pandemic-era buyer. Only 17% of that cohort has transacted again. This high retention is characteristic of the 2–4 year holding period identified in our earlier research — owners are not yet at the five-year threshold where necessity begins to overtake inertia.
2020 buyers hit five years in 2025. 2021 buyers follow in 2026. The resale clock, reset by the pandemic, is now approaching its natural release point.
The four-year price performance from the 2020 base year illustrates the structural divergence between flat owners and house owners — a divergence that directly determines the cohort's capacity and willingness to sell.
Median price growth 2020–2024, England & Wales. HMLR Price Paid Data.
Every other property type outperformed flats over this period, often by a factor of two or more. The gap is not a short-term blip. It reflects structural headwinds unique to leasehold flats: the EPC compliance burden, cladding remediation costs in post-Grenfell blocks, and a buyer pool constrained by mortgage lender caution on high-rise and short-lease stock.
Premonitia's ownership-cycle model identifies the five-year holding mark as the primary inflection point for flat seller probability. As 282,850 pandemic-era flat owners reach that threshold over the next 18 months, the model anticipates a significant uplift in motivated-seller signals across inner and outer London.
Unlike conventional canvassing that relies on visible listing activity, Premonitia identifies this cohort by cross-referencing purchase date, property type, leasehold duration, local price performance, and service charge trajectory — generating a ranked probability score before the owner has contacted an agent.
Agents with access to Premonitia's scored dataset are positioned to reach these owners six to twelve months before they appear on a competitor's phone list.
Analysis is based on HMLR Price Paid Data (PPD), comprising 31 million residential property transactions in England & Wales from 1995 to Q4 2024. Flat transactions are identified by property type code "F". Covid cohort retention is measured by matching subsequent sale records to the same address (PAON, SAON, postcode). Where no subsequent record exists the property is classified as still held. Median prices use the 50th percentile of all transactions within the year and property type. All figures are nominal; no inflation adjustment is applied.